Developing a Local Capability for the Manufacture 9f Activated Carbon from Agricultural Waste.

ABSTRACT Commercial act~vated carbons are produced from bituminous and lignite coal. The environmental impacts and potentially increasing cost of coal has encouraged the search for other alternatives in agricultural wastes. The objectives of this study were to develop process flow diagrams for the large scale production of activated carbon from three agricultural wastes namely: coconut shells, oil-palm shells, and sugarcane bagasse as well as carrying out an economic evaluation to estimate the cost to manufacture these activated carbons. Process flow diagrams were developed for the steam activation of coconut shells, steam activation of sugarcane bagasse and phosphoric acid activation of oil-palm shells. Process parameters were calculated for a production facility of 10,000 kg of each of the raw materials per day. Final product yields were approximately 50% for steam activation of coconut shell, 19.4% for steam activation of sugarcane bagasse, and 30% for the phosphoric activation of oil-palm shell. Therefore 5000Kg of the steam activated coconut shell, 1940Kg of the steam activated sugarcane bagasse and 3000Kg of phosphoric activated oil-palm shell could be produced per day. Mass losses were however incurred in the milling process (about 20%), during pyrolysis (about 65% for steam activation af coconut shell, 70% for steam activation of oil palm shell and 75% for phosphoric activation of sugarcane bagasse), during washing drying (about 13% in all) and during sieving(about 5% in all).